Roma is not that strong and they're not stable but if they take this match very serious, they can achieve victory. Porto isn't a strong team too and I believe that whoever among these two clubs that can outplay the other will definitely qualify to the round of 16. I will both clubs have the same strength and it's a perfect match.
Both teams will build attacks very well because it is about who will qualify for the next round and who will be eliminated in this season in the Europa League early. So I also think that the Porto vs Roma match will be a pretty fierce match for these two teams because apart from their respective strengths, it is also about how they implement their best strategy in the match so that they do not lose badly. But I want to see Roma advance to the next round so that Roma can have the spirit to continue competing with stronger teams in the next round.
This two teams from my own stand point have equal chances in this match following their respective performance so far in the Europa League. This two will have to prove who understands each other better because from every stand point it is difficult to predict which club will outplay the other.